drivers/acpi/hardware/hwsleep.c

   1
   2 /******************************************************************************
   3  *
   4  * Name: hwsleep.c - ACPI Hardware Sleep/Wake Interface
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2007, R. Byron Moore
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include <acpi/actables.h>
  47
  48 #define _COMPONENT          ACPI_HARDWARE
  49 ACPI_MODULE_NAME("hwsleep")
  50
  51 /*******************************************************************************
  52  *
  53  * FUNCTION:    acpi_set_firmware_waking_vector
  54  *
  55  * PARAMETERS:  physical_address    - Physical address of ACPI real mode
  56  *                                    entry point.
  57  *
  58  * RETURN:      Status
  59  *
  60  * DESCRIPTION: Access function for the firmware_waking_vector field in FACS
  61  *
  62  ******************************************************************************/
  63 acpi_status
  64 acpi_set_firmware_waking_vector(acpi_physical_address physical_address)
  65 {
  66         struct acpi_table_facs *facs;
  67         acpi_status status;
  68
  69         ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector);
  70
  71         /* Get the FACS */
  72
  73         status =
  74             acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
  75                                     (struct acpi_table_header **)&facs);
  76         if (ACPI_FAILURE(status)) {
  77                 return_ACPI_STATUS(status);
  78         }
  79
  80         /* Set the vector */
  81
  82         if ((facs->length < 32) || (!(facs->xfirmware_waking_vector))) {
  83                 /*
  84                  * ACPI 1.0 FACS or short table or optional X_ field is zero
  85                  */
  86                 facs->firmware_waking_vector = (u32) physical_address;
  87         } else {
  88                 /*
  89                  * ACPI 2.0 FACS with valid X_ field
  90                  */
  91                 facs->xfirmware_waking_vector = physical_address;
  92         }
  93
  94         return_ACPI_STATUS(AE_OK);
  95 }
  96
  97 ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector)
  98
  99 /*******************************************************************************
 100  *
 101  * FUNCTION:    acpi_get_firmware_waking_vector
 102  *
 103  * PARAMETERS:  *physical_address   - Where the contents of
 104  *                                    the firmware_waking_vector field of
 105  *                                    the FACS will be returned.
 106  *
 107  * RETURN:      Status, vector
 108  *
 109  * DESCRIPTION: Access function for the firmware_waking_vector field in FACS
 110  *
 111  ******************************************************************************/
 112 #ifdef ACPI_FUTURE_USAGE
 113 acpi_status
 114 acpi_get_firmware_waking_vector(acpi_physical_address * physical_address)
 115 {
 116         struct acpi_table_facs *facs;
 117         acpi_status status;
 118
 119         ACPI_FUNCTION_TRACE(acpi_get_firmware_waking_vector);
 120
 121         if (!physical_address) {
 122                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 123         }
 124
 125         /* Get the FACS */
 126
 127         status =
 128             acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
 129                                     (struct acpi_table_header **)&facs);
 130         if (ACPI_FAILURE(status)) {
 131                 return_ACPI_STATUS(status);
 132         }
 133
 134         /* Get the vector */
 135
 136         if ((facs->length < 32) || (!(facs->xfirmware_waking_vector))) {
 137                 /*
 138                  * ACPI 1.0 FACS or short table or optional X_ field is zero
 139                  */
 140                 *physical_address =
 141                     (acpi_physical_address) facs->firmware_waking_vector;
 142         } else {
 143                 /*
 144                  * ACPI 2.0 FACS with valid X_ field
 145                  */
 146                 *physical_address =
 147                     (acpi_physical_address) facs->xfirmware_waking_vector;
 148         }
 149
 150         return_ACPI_STATUS(AE_OK);
 151 }
 152
 153 ACPI_EXPORT_SYMBOL(acpi_get_firmware_waking_vector)
 154 #endif
 155 /*******************************************************************************
 156  *
 157  * FUNCTION:    acpi_enter_sleep_state_prep
 158  *
 159  * PARAMETERS:  sleep_state         - Which sleep state to enter
 160  *
 161  * RETURN:      Status
 162  *
 163  * DESCRIPTION: Prepare to enter a system sleep state (see ACPI 2.0 spec p 231)
 164  *              This function must execute with interrupts enabled.
 165  *              We break sleeping into 2 stages so that OSPM can handle
 166  *              various OS-specific tasks between the two steps.
 167  *
 168  ******************************************************************************/
 169 acpi_status acpi_enter_sleep_state_prep(u8 sleep_state)
 170 {
 171         acpi_status status;
 172         struct acpi_object_list arg_list;
 173         union acpi_object arg;
 174
 175         ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_prep);
 176
 177         /*
 178          * _PSW methods could be run here to enable wake-on keyboard, LAN, etc.
 179          */
 180         status = acpi_get_sleep_type_data(sleep_state,
 181                                           &acpi_gbl_sleep_type_a,
 182                                           &acpi_gbl_sleep_type_b);
 183         if (ACPI_FAILURE(status)) {
 184                 return_ACPI_STATUS(status);
 185         }
 186
 187         /* Setup parameter object */
 188
 189         arg_list.count = 1;
 190         arg_list.pointer = &arg;
 191
 192         arg.type = ACPI_TYPE_INTEGER;
 193         arg.integer.value = sleep_state;
 194
 195         /* Run the _PTS and _GTS methods */
 196
 197         status = acpi_evaluate_object(NULL, METHOD_NAME__PTS, &arg_list, NULL);
 198         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 199                 return_ACPI_STATUS(status);
 200         }
 201
 202         status = acpi_evaluate_object(NULL, METHOD_NAME__GTS, &arg_list, NULL);
 203         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 204                 return_ACPI_STATUS(status);
 205         }
 206
 207         /* Setup the argument to _SST */
 208
 209         switch (sleep_state) {
 210         case ACPI_STATE_S0:
 211                 arg.integer.value = ACPI_SST_WORKING;
 212                 break;
 213
 214         case ACPI_STATE_S1:
 215         case ACPI_STATE_S2:
 216         case ACPI_STATE_S3:
 217                 arg.integer.value = ACPI_SST_SLEEPING;
 218                 break;
 219
 220         case ACPI_STATE_S4:
 221                 arg.integer.value = ACPI_SST_SLEEP_CONTEXT;
 222                 break;
 223
 224         default:
 225                 arg.integer.value = ACPI_SST_INDICATOR_OFF;     /* Default is off */
 226                 break;
 227         }
 228
 229         /* Set the system indicators to show the desired sleep state. */
 230
 231         status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
 232         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 233                 ACPI_EXCEPTION((AE_INFO, status,
 234                                 "While executing method _SST"));
 235         }
 236
 237         /*
 238          * 1) Disable/Clear all GPEs
 239          */
 240         status = acpi_hw_disable_all_gpes();
 241         if (ACPI_FAILURE(status)) {
 242                 return_ACPI_STATUS(status);
 243         }
 244
 245         return_ACPI_STATUS(AE_OK);
 246 }
 247
 248 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_prep)
 249
 250 /*******************************************************************************
 251  *
 252  * FUNCTION:    acpi_enter_sleep_state
 253  *
 254  * PARAMETERS:  sleep_state         - Which sleep state to enter
 255  *
 256  * RETURN:      Status
 257  *
 258  * DESCRIPTION: Enter a system sleep state (see ACPI 2.0 spec p 231)
 259  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 260  *
 261  ******************************************************************************/
 262 acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
 263 {
 264         u32 PM1Acontrol;
 265         u32 PM1Bcontrol;
 266         struct acpi_bit_register_info *sleep_type_reg_info;
 267         struct acpi_bit_register_info *sleep_enable_reg_info;
 268         u32 in_value;
 269         acpi_status status;
 270
 271         ACPI_FUNCTION_TRACE(acpi_enter_sleep_state);
 272
 273         if ((acpi_gbl_sleep_type_a > ACPI_SLEEP_TYPE_MAX) ||
 274             (acpi_gbl_sleep_type_b > ACPI_SLEEP_TYPE_MAX)) {
 275                 ACPI_ERROR((AE_INFO, "Sleep values out of range: A=%X B=%X",
 276                             acpi_gbl_sleep_type_a, acpi_gbl_sleep_type_b));
 277                 return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 278         }
 279
 280         sleep_type_reg_info =
 281             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE_A);
 282         sleep_enable_reg_info =
 283             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
 284
 285         /* Clear wake status */
 286
 287         status = acpi_set_register(ACPI_BITREG_WAKE_STATUS, 1);
 288         if (ACPI_FAILURE(status)) {
 289                 return_ACPI_STATUS(status);
 290         }
 291
 292         /* Clear all fixed and general purpose status bits */
 293
 294         status = acpi_hw_clear_acpi_status();
 295         if (ACPI_FAILURE(status)) {
 296                 return_ACPI_STATUS(status);
 297         }
 298
 299         /*
 300          * 2) Enable all wakeup GPEs
 301          */
 302         status = acpi_hw_disable_all_gpes();
 303         if (ACPI_FAILURE(status)) {
 304                 return_ACPI_STATUS(status);
 305         }
 306
 307         acpi_gbl_system_awake_and_running = FALSE;
 308
 309         status = acpi_hw_enable_all_wakeup_gpes();
 310         if (ACPI_FAILURE(status)) {
 311                 return_ACPI_STATUS(status);
 312         }
 313
 314         /* Get current value of PM1A control */
 315
 316         status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK,
 317                                        ACPI_REGISTER_PM1_CONTROL, &PM1Acontrol);
 318         if (ACPI_FAILURE(status)) {
 319                 return_ACPI_STATUS(status);
 320         }
 321         ACPI_DEBUG_PRINT((ACPI_DB_INIT,
 322                           "Entering sleep state [S%d]\n", sleep_state));
 323
 324         /* Clear SLP_EN and SLP_TYP fields */
 325
 326         PM1Acontrol &= ~(sleep_type_reg_info->access_bit_mask |
 327                          sleep_enable_reg_info->access_bit_mask);
 328         PM1Bcontrol = PM1Acontrol;
 329
 330         /* Insert SLP_TYP bits */
 331
 332         PM1Acontrol |=
 333             (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
 334         PM1Bcontrol |=
 335             (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
 336
 337         /*
 338          * We split the writes of SLP_TYP and SLP_EN to workaround
 339          * poorly implemented hardware.
 340          */
 341
 342         /* Write #1: fill in SLP_TYP data */
 343
 344         status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
 345                                         ACPI_REGISTER_PM1A_CONTROL,
 346                                         PM1Acontrol);
 347         if (ACPI_FAILURE(status)) {
 348                 return_ACPI_STATUS(status);
 349         }
 350
 351         status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
 352                                         ACPI_REGISTER_PM1B_CONTROL,
 353                                         PM1Bcontrol);
 354         if (ACPI_FAILURE(status)) {
 355                 return_ACPI_STATUS(status);
 356         }
 357
 358         /* Insert SLP_ENABLE bit */
 359
 360         PM1Acontrol |= sleep_enable_reg_info->access_bit_mask;
 361         PM1Bcontrol |= sleep_enable_reg_info->access_bit_mask;
 362
 363         /* Write #2: SLP_TYP + SLP_EN */
 364
 365         ACPI_FLUSH_CPU_CACHE();
 366
 367         status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
 368                                         ACPI_REGISTER_PM1A_CONTROL,
 369                                         PM1Acontrol);
 370         if (ACPI_FAILURE(status)) {
 371                 return_ACPI_STATUS(status);
 372         }
 373
 374         status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
 375                                         ACPI_REGISTER_PM1B_CONTROL,
 376                                         PM1Bcontrol);
 377         if (ACPI_FAILURE(status)) {
 378                 return_ACPI_STATUS(status);
 379         }
 380
 381         if (sleep_state > ACPI_STATE_S3) {
 382                 /*
 383                  * We wanted to sleep > S3, but it didn't happen (by virtue of the
 384                  * fact that we are still executing!)
 385                  *
 386                  * Wait ten seconds, then try again. This is to get S4/S5 to work on
 387                  * all machines.
 388                  *
 389                  * We wait so long to allow chipsets that poll this reg very slowly to
 390                  * still read the right value. Ideally, this block would go
 391                  * away entirely.
 392                  */
 393                 acpi_os_stall(10000000);
 394
 395                 status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
 396                                                 ACPI_REGISTER_PM1_CONTROL,
 397                                                 sleep_enable_reg_info->
 398                                                 access_bit_mask);
 399                 if (ACPI_FAILURE(status)) {
 400                         return_ACPI_STATUS(status);
 401                 }
 402         }
 403
 404         /* Wait until we enter sleep state */
 405
 406         do {
 407                 status = acpi_get_register(ACPI_BITREG_WAKE_STATUS, &in_value);
 408                 if (ACPI_FAILURE(status)) {
 409                         return_ACPI_STATUS(status);
 410                 }
 411
 412                 /* Spin until we wake */
 413
 414         } while (!in_value);
 415
 416         return_ACPI_STATUS(AE_OK);
 417 }
 418
 419 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state)
 420
 421 /*******************************************************************************
 422  *
 423  * FUNCTION:    acpi_enter_sleep_state_s4bios
 424  *
 425  * PARAMETERS:  None
 426  *
 427  * RETURN:      Status
 428  *
 429  * DESCRIPTION: Perform a S4 bios request.
 430  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 431  *
 432  ******************************************************************************/
 433 acpi_status asmlinkage acpi_enter_sleep_state_s4bios(void)
 434 {
 435         u32 in_value;
 436         acpi_status status;
 437
 438         ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_s4bios);
 439
 440         status = acpi_set_register(ACPI_BITREG_WAKE_STATUS, 1);
 441         if (ACPI_FAILURE(status)) {
 442                 return_ACPI_STATUS(status);
 443         }
 444
 445         status = acpi_hw_clear_acpi_status();
 446         if (ACPI_FAILURE(status)) {
 447                 return_ACPI_STATUS(status);
 448         }
 449
 450         /*
 451          * 1) Disable/Clear all GPEs
 452          * 2) Enable all wakeup GPEs
 453          */
 454         status = acpi_hw_disable_all_gpes();
 455         if (ACPI_FAILURE(status)) {
 456                 return_ACPI_STATUS(status);
 457         }
 458         acpi_gbl_system_awake_and_running = FALSE;
 459
 460         status = acpi_hw_enable_all_wakeup_gpes();
 461         if (ACPI_FAILURE(status)) {
 462                 return_ACPI_STATUS(status);
 463         }
 464
 465         ACPI_FLUSH_CPU_CACHE();
 466
 467         status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
 468                                     (u32) acpi_gbl_FADT.S4bios_request, 8);
 469
 470         do {
 471                 acpi_os_stall(1000);
 472                 status = acpi_get_register(ACPI_BITREG_WAKE_STATUS, &in_value);
 473                 if (ACPI_FAILURE(status)) {
 474                         return_ACPI_STATUS(status);
 475                 }
 476         } while (!in_value);
 477
 478         return_ACPI_STATUS(AE_OK);
 479 }
 480
 481 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_s4bios)
 482
 483 /*******************************************************************************
 484  *
 485  * FUNCTION:    acpi_leave_sleep_state
 486  *
 487  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 488  *
 489  * RETURN:      Status
 490  *
 491  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 492  *              Called with interrupts ENABLED.
 493  *
 494  ******************************************************************************/
 495 acpi_status acpi_leave_sleep_state(u8 sleep_state)
 496 {
 497         struct acpi_object_list arg_list;
 498         union acpi_object arg;
 499         acpi_status status;
 500         struct acpi_bit_register_info *sleep_type_reg_info;
 501         struct acpi_bit_register_info *sleep_enable_reg_info;
 502         u32 PM1Acontrol;
 503         u32 PM1Bcontrol;
 504
 505         ACPI_FUNCTION_TRACE(acpi_leave_sleep_state);
 506
 507         /*
 508          * Set SLP_TYPE and SLP_EN to state S0.
 509          * This is unclear from the ACPI Spec, but it is required
 510          * by some machines.
 511          */
 512         status = acpi_get_sleep_type_data(ACPI_STATE_S0,
 513                                           &acpi_gbl_sleep_type_a,
 514                                           &acpi_gbl_sleep_type_b);
 515         if (ACPI_SUCCESS(status)) {
 516                 sleep_type_reg_info =
 517                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE_A);
 518                 sleep_enable_reg_info =
 519                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
 520
 521                 /* Get current value of PM1A control */
 522
 523                 status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK,
 524                                                ACPI_REGISTER_PM1_CONTROL,
 525                                                &PM1Acontrol);
 526                 if (ACPI_SUCCESS(status)) {
 527
 528                         /* Clear SLP_EN and SLP_TYP fields */
 529
 530                         PM1Acontrol &= ~(sleep_type_reg_info->access_bit_mask |
 531                                          sleep_enable_reg_info->
 532                                          access_bit_mask);
 533                         PM1Bcontrol = PM1Acontrol;
 534
 535                         /* Insert SLP_TYP bits */
 536
 537                         PM1Acontrol |=
 538                             (acpi_gbl_sleep_type_a << sleep_type_reg_info->
 539                              bit_position);
 540                         PM1Bcontrol |=
 541                             (acpi_gbl_sleep_type_b << sleep_type_reg_info->
 542                              bit_position);
 543
 544                         /* Just ignore any errors */
 545
 546                         (void)acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
 547                                                      ACPI_REGISTER_PM1A_CONTROL,
 548                                                      PM1Acontrol);
 549                         (void)acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
 550                                                      ACPI_REGISTER_PM1B_CONTROL,
 551                                                      PM1Bcontrol);
 552                 }
 553         }
 554
 555         /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
 556
 557         acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
 558
 559         /* Setup parameter object */
 560
 561         arg_list.count = 1;
 562         arg_list.pointer = &arg;
 563         arg.type = ACPI_TYPE_INTEGER;
 564
 565         /* Ignore any errors from these methods */
 566
 567         arg.integer.value = ACPI_SST_WAKING;
 568         status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
 569         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 570                 ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
 571         }
 572
 573         arg.integer.value = sleep_state;
 574         status = acpi_evaluate_object(NULL, METHOD_NAME__BFS, &arg_list, NULL);
 575         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 576                 ACPI_EXCEPTION((AE_INFO, status, "During Method _BFS"));
 577         }
 578
 579         /*
 580          * GPEs must be enabled before _WAK is called as GPEs
 581          * might get fired there
 582          *
 583          * Restore the GPEs:
 584          * 1) Disable/Clear all GPEs
 585          * 2) Enable all runtime GPEs
 586          */
 587         status = acpi_hw_disable_all_gpes();
 588         if (ACPI_FAILURE(status)) {
 589                 return_ACPI_STATUS(status);
 590         }
 591         status = acpi_hw_enable_all_runtime_gpes();
 592         if (ACPI_FAILURE(status)) {
 593                 return_ACPI_STATUS(status);
 594         }
 595
 596         status = acpi_evaluate_object(NULL, METHOD_NAME__WAK, &arg_list, NULL);
 597         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 598                 ACPI_EXCEPTION((AE_INFO, status, "During Method _WAK"));
 599         }
 600         /* TBD: _WAK "sometimes" returns stuff - do we want to look at it? */
 601
 602         acpi_gbl_system_awake_and_running = TRUE;
 603
 604         /* Enable power button */
 605
 606         (void)
 607             acpi_set_register(acpi_gbl_fixed_event_info
 608                               [ACPI_EVENT_POWER_BUTTON].enable_register_id, 1);
 609
 610         (void)
 611             acpi_set_register(acpi_gbl_fixed_event_info
 612                               [ACPI_EVENT_POWER_BUTTON].status_register_id, 1);
 613
 614         arg.integer.value = ACPI_SST_WORKING;
 615         status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
 616         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 617                 ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
 618         }
 619
 620         return_ACPI_STATUS(status);
 621 }
 622
 623 ACPI_EXPORT_SYMBOL(acpi_leave_sleep_state)